Local residents may soon know the opening date for the long-anticipated Silver Line.

Officials with the Metropolitan Washington Airports Authority, which is overseeing construction of the rail line, said they believe final construction work is on track to reach a key milestone next week.

The $2.9 billion first phase of the Silver Line includes four stations in Tysons Corner and one in Reston.

On Monday, Washington Metropolitan Area Transit Authority General Manager Richard Sarles said the agency expects to declare that the Silver Line has met “operational readiness” standards on May 27, presuming that the airports authority and its contractor Dulles Transit Partners continue to stay on track.

The rail line was originally planned to begin passenger service at the end of 2013, but a series of construction delays and the correction of problems identified during testing have left the start date an open question.

Problems with the automatic train control system were a chief cause of delays. Dulles Transit Partners has also had to go back and replace some items, such as public address system loudspeakers and cables, that didn’t meet inspection requirements and held up the occupancy permits for the new stations and some other facilities.

The contractor is continuing to complete that work under the terms of an agreement between the airports authority and Metro to keep the project moving forward.

“We’re optimistic about the state of the project and the ability to get to what Metro needs,” said Chris Paolino, an airports authority spokesman.

Despite the ongoing work, the total cost of the project is not expected to exceed its current budget, Paolino said.

Once Metro declares operational readiness, it will initiate a 90-day period for testing the system, conducting emergency drills and training employees on the new line. The Federal Transit Administration and the Tri-State Oversight Committee, which oversees Metro, will also conduct safety reviews during this time period.

The WMATA Board of Directors must also formally accept the Silver Line into the Metro system and set the date for the start of service.

The airports authority is also overseeing the ongoing construction work for the second phase of the Silver Line, which will include stops in Reston, Herndon, at Washington Dulles International Airport and in Loudoun County.